The present invention relates to new metallocene catalysts for use in preparation of olefin or styrene polymers and polymerization methods using the metallocene catalysts. More specifically, the present invention relates to new metallocene catalysts which are capable of preparing olefin or styrene polymers having a high activity, a good stereoregularity, a high melting point, and a good molecular weight distribution in the presence of a small amount of a co-catalyst. The present invention also relates to polymerization method for preparing such olefin or styrene polymers using the metallocene catalysts.
Olefin or styrene polymers are generally prepared by radical polymerization, ionic polymerization, or coordination polymerization using a Ziegler-Natta catalyst. Radical or ionic polymerization provides olefin or styrene polymers having mainly an atactic structure. Coordination polymerization using a Ziegler-Natta catalyst provides olefin or styrene polymers having mainly an isotactic structure.
The polymers are structurally divided into three groups such as atactic polymers, isotactic polymers, and syndiotactic polymers, depending on the position of benzene rings as a side chain in relation to a main chain of molecular structure of the polymers. An atactic structure means that configuration of side chains is irregular. An isotactic structure means that side chains are positioned at one side relative to a main chain. A syndiotactic structure means that side chains are alternatively arranged for a main chain.
The polymers having a syndiotactic structure have been only theoretically known, and practically not prepared until a metallocene catalyst was employed to the preparation methods.
Development of the metallocene catalysts was to provide a syndiotactic polystyrene having a stereoregularity or polyolefins having improved physical properties. The conventional metallocene catalysts have a structure which a Group IV transition metal compound of the Periodic Table of Elements is coordinated with ligands composed of one or two cycloalkanedienyl groups or their derivatives. The Group IV transition b metal of the Periodic Table of Elements contain titanium, zirconium, hafnium, etc. The cycloalkanedienyl groups include a cyclopentadienyl group, an indenyl group, a fluorenyl group, etc.
The metallocene catalysts are usually employed with a co-catalyst. The conventionally used Ziegler-Natta catalysts system is composed of a halogenated titanium compound as a main catalyst and alkylaluminium as a co-catalyst. Example of the halogenated titanium compound is titanium tetrachloride. Example of alkylaluminium is trimethylaluminium and triethylaluminium.
While, recently developed metallocene catalyst system is employed with alkylaluminoxane as a co-catalyst, which is capable of preparing polystyrenes having a stereoregularity or polyolefins having improved physical properties. Alkylaluminoxane is produced by reacting alkylaluminium with H2O. Especially, syndiotactic polystyrene has a structure which benzene rings as a side chain is alternatively positioned relative to a main chain of the polymer. The syndiotactic polystyrene has an excellent heat-resistance and physical properties since the polymer has about 270xc2x0 C. of a melting point (Tm) due to stereoregularity comparing with the conventional amorphous atactic polystyrene, which is of interest.
European Patent Publication No. 210 615 A2 (1987) discloses a syndiotactic polystyrene having a stereoregularity. Also, the patent discloses cyclopentadienyltitanium trichloride and an alkyl-substituted cyclopentadienyltitanium trichloride such as pentamethylcyclopentadienyltitanium trichloride to prepare syndiotactic polystyrenes. It is known that the metallocene catalysts have a good activity, molecular weight distribution, and syndiotactic index.
U.S. Pat. No. 4,544,762 discloses a preparation method of aluminoxane which can be used as a component of catalysts in the preparation of highly active and homogeneous Ziegler-Natta catalysts.
U.S. Pat. No. 5,026,798 discloses a process for polymerizing xcex1-olefins which utilize certain monocyclopentadienyl metal compounds of a Group IVb transition metal of the Periodic Table of Elements in an aluminoxane activated catalyst system to produce crystalline poly-xcex1-olefins.
U.S. Pat. Nos. 08/844,109 and 08/844,110 disclose a new alkyl bridged binuclear metallocene catalyst (ABBM), silyl bridged binuclear metallocene catalyst (SBBM), and alkyl-silyl bridged binuclear metallocene catalyst (A-SBBM) for preparing a syndiotactic polystyrene having a high activity, a good stereoregularity, a high melting point, and a good molecular weight distribution.
Accordingly, the present inventors have developed new metallocene catalysts for use in preparation of olefin or styrene polymers and polymerization methods for effectively preparing such olefin or styrene polymers using the metallocene catalysts.
An object of the present invention is to provide metallocene catalysts which are capable of preparing olefin or styrene polymers having a high activity, a good stereoregularity, a high melting point, and a good molecular weight distribution.
Another object of the present invention is to provide highly active metallocene catalysts which are capable of preparing a large amount of olefin or styrene polymers in the presence of a small amount of a co-catalyst.
A further object of the present invention is to provide preparation methods of metallocene catalyst and polymerization methods for effectively preparing olefin or styrene polymers using the metallocene catalysts.
Other objects and advantages of this invention will be apparent from the ensuing disclosure and appended claims.
The new metallocene catalysts according to the present invention are prepared by reacting a metallocene compound with a compound having at least two functional groups. The metallocene compound is a transition metal compound which a transition metal is coordinated with a main ligand such as cycloalkanedienyl group and an ancillary ligand. Functional groups in the compound having at least two functional groups are selected from the group consisting of a hydroxy group, a thiol group, a primary amine group, a secondary amine group, etc.
The metallocene catalysts of the present invention can be prepared by reacting a metallocene compound with a dianion compound produced by reacting an alkali metal compound with a compound having those functional groups.
The metallocene catalysts according to the present invention have a structure which an ancillary ligand of a metallocene compound is bonded to the functional groups of a compound having at least two functional groups. A structure of the metallocene catalysts can be varied according to the type of metallocene compounds, the type of the compound having at least two functional groups, and the molar ratio of each reactant.
The metallocene catalyst is employed with a co-catalyst for styrene or olefin polymerization. The co-catalyst is an organometallic compound or a mixture of non-coordinated Lewis acid and alkylaluminium as it is widely known. The organometallic compound is usually alkylaluminoxane or organoaluminium compound.
The syndiotactic polystyrenes or polyolefins having high physical properties are prepared by using the catalyst system composed of a metallocene catalyst according to the present invention and a co-catalyst. The monomers for polymerization include styrene, styrene derivatives, or a compound having ethylenically unsaturated double bonds. Those compounds are homopolymerized or copolymerized to give polystyrene or polyolefin having a high activity, a good stereoregularity, a high melting point, and a good molecular weight distribution.
The metallocene catalyst according to the present invention is prepared by reacting a metallocene compound with a compound having at least two functional groups. The metallocene catalyst has a structure which an ancillary ligand of a metallocene compound is coordinated with a functional group of a compound having at least two functional groups.
The metallocene compound of the present invention is represented by the following general formulae (A) or (B). The compound having at least two functional groups is represented by the following general formulae (C), (D), or (E). 
wherein M in the formulae (A) and (B) represents a transition metal of a Group IV, V or VI of the Periodic Table and preferably of a Group IV such as titanium, zirconium or hafnium; R1, R2, R3 and R4 are respectively a hydrogen atom; a halogen atom; an alkyl group, a cycloalkyl group or an alkoxy group of C1-20; an aryl group, an alkylaryl group or an arylalkyl group of C6-20; a cyclopentadienyl group; a substituted cyclopentadienyl group; an indenyl group; a substituted indenyl group; a fluorenyl group; or a substituted fluorenyl group; a, b and c are respectively an integer of 0 to 4; and d and e are respectively an integer of 0 to 3.
T1, T2, T3, and T4 in the formulae (C), (D), and (E) respectfully represent a hydrogen atom; an alkyl group, a cycloalkyl group, and an alkoxy group of C1-20; an aryl group, an alkyaryl group, or an arylalkyl group of C6-20; or an alkali metal such as Na, Li, K, etc. Y, Yxe2x80x2, Yxe2x80x3, and Yxe2x80x2xe2x80x3 are respectively of O, S, xe2x80x94Nr17, or xe2x80x94Pr18 (wherein r17 and r18 are respectively a hydrogen atom; an alkyl group, a cycloalkyl group, and an alkoxy group of C1-10; an aryl group of, an alkyaryl group, and an arylalkyl group of C6-20) R5, R6, R7, and R8 are respectively Rxe2x80x2, Rxe2x80x2-m-Rxe2x80x3, and 
wherein Rxe2x80x2, Rxe2x80x3, Rxe2x80x2xe2x80x3, and Rxe2x80x3xe2x80x3 are selected from the group consisting of a linear alkylene group and a branched alkylene group of C6-20; a cycloalkylene group or a substituted cycloalkylene group of C3-20; an arylene group; an alkyarylene group, and an arylalkylene group of C6-40; and r19 is a hydrogen atom; an alkyl group, a cycloalkyl group and an alkoxy group of C1-10; and an aryl group; an alkyaryl group, and an arylakyl group of C6-20; and m is an oxygen atom, a sulfur atom, xe2x80x94Nr17 or xe2x80x94Pr18, and Sir17r18, wherein r17 and r18 are respectively a hydrogen atom; an alkyl group, a cycloalkyl group and an alkoxy group of C1-10; or an aryl group, an alkylaryl group or an arylalkyl group of C6-20.
Q is N or xe2x80x94Cr20 (r20 is an alkyl group, a cycloalkyl group or an alkoxy group of C1xcx9c10; or an aryl group, an alkylaryl group or an arylalkyl group of C6xcx9c20); and 
The representative examples of the metallocene catalysts according to the present invention are represented by the following general formulae (I)xcx9c(V): 
wherein M, Mxe2x80x2, Mxe2x80x3 and Mxe2x80x2xe2x80x3 in the general formulae (I)xcx9c(V) are respectively a transition metal of a Group IV, V, or VI of the Periodic Table and preferably of a Group IV such as titanium, zirconium or hafnium;
Cp, Cpxe2x80x2, Cpxe2x80x3 and Cpxe2x80x2xe2x80x3 are respectively a cyclopentadienyl group, an indenyl group, a fluorenyl group or a derivative of each group which forms xcex75-bond with a transition metal such as M, Mxe2x80x2, Mxe2x80x3 and Mxe2x80x2xe2x80x3, also, Cp, Cpxe2x80x2, Cpxe2x80x3 and Cpxe2x80x2xe2x80x3 are represented by the general formulae (a), (b), (c) or (d); 
(wherein r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15 and r16 are respectively a hydrogen atom; an alkyl group, a cycloalkyl group or an alkoxy group of C1xcx9c20; or an aryl group, an alkylaryl group or an arylalkyl group of C1xcx9c20; and f is an integer of 4 to 8.)
X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11 and X12 are respectively a hydrogen atom; a hydroxy group; a halogen atom; an alkyl group, a cycloalkyl group or an alkoxy group of C1xcx9c20; or an aryl group, an alkylaryl group or an arylalkyl group of C1xcx9c40;
G, Gxe2x80x2 and Gxe2x80x3 are the groups connecting between two transition metals and are represented as xe2x80x94YR5Yxe2x80x2xe2x80x94 or T2xe2x80x94YR5Yxe2x80x2xe2x80x94T1 (wherein T1 and T2 represent respectively a hydrogen atom; and alkyl group, a cycloalkyl group or an alkoxy group of C1-20; or an aryl group, an alkylaryl group or an arylalkyl group of C6-20);
Y, Yxe2x80x2, Yxe2x80x3, and Yxe2x80x2xe2x80x3 are respectively of O, S, xe2x80x94Nr17, or xe2x80x94Pr18 (wherein and r17 and r18 are respectively a hydrogen atom; an alkyl group, a cycloalkyl group, and an alkoxy group of C1-10; an aryl group of, an alkyaryl group, and an arylalkyl group of C6-20). R5 is Rxe2x80x2, Rxe2x80x2-m-Rxe2x80x3, and 
wherein Rxe2x80x2, Rxe2x80x3, Rxe2x80x2xe2x80x3, and Rxe2x80x3xe2x80x3 are selected from the group consisting of a linear alkylene group and a branched alkylene group of C6-20; a cycloalkylene group or substituted cycloalkylene group of C3-20; an arylene group; an alkyarylene group, and an arylalkylene group of C6-40. r19 is a hydrogen atom, an alkyl group, a cycloalkyl group and an alkoxy group of C1-10; and an aryl group; an alkyaryl group, and an arylakyl group of C6-20. m is an oxygen atom, a sulfur atom, xe2x80x94Nr17 or xe2x80x94Pr18, and Sir17r18, wherein r17 and r18 are respectively a hydrogen atom; an alkyl group, a cycloalkyl group or an alkoxy group of C1-10; or an aryl group, an alkylaryl group or an aryl group of C6-20.
Q is N or xe2x80x94Cr20 (wherein r20 is a hydrogen atom; an alkyl group, a cycloalkyl group or an alkoxy group of C1xcx9c10; or an aryl group, an alkylaryl group or an arylalkyl group of C6xcx9c20); and 
A metallocene compound used for preparing the metallocene catalyst according to the present invention is commercially available. Also, the metallocene compound may be prepared according to a method which is conventionally well known. The metallocene compound can be prepared by the steps comprising; preparing a salt of a substituted cyclopentadienyl ligand containing alkali metal by reacting the corresponding cyclopentadienyl ligand with an alkali metal or an alkali metal compound, introducing a silicon compound or tin compound to the salt of a substituted cyclopentadienyl ligand, and reacting the above resultant compound with a Group IV transition metal compound.
In case of substituting an ancillary ligand of a metallocene compound with an alkoxy group, an alkyl group, or any other groups, the metallocene compound is reacted with the desired equivalent of alcohol or alkyl metal compound. The above-described method for preparing a metallocene compound may be easily performed by an ordinary skilled person in the art.
The alkali metals or alkali metal compounds include K, Na, n-butyllithium, sec-butyllithium, tert-butyllithium, methyllithium, sodium methoxide, sodium ethoxide, etc.
The Group IV transition metal compound of the Periodic Table of Elements include titanium tetrachloride, zirconium tetrachloride, and hafnium tetrachloride.
The representative examples of the metallocene compound represented by the general formula (A) or (B) include:
pentamethylcyclopentadienyltitanium trichloride,
pentamethylcyclopentadienylmethoxytitanium dichloride,
pentamethylcyclopentadienyldimethoxytitanium monochloride,
1,2,3,4-tetramethylcyclopentadienyltitanium trichloride,
1,2,3,4-tetramethylcyclopentadienylmethoxytitanium dichloride,
1,2,3,4-tetramethylcyclopentadienyldimethoxytitanium monochloride,
1,2,4-trimethylcyclopentadienyltitanium trichloride,
1,2,4-trimethylcyclopentadienylmethoxytitanium dichloride,
1,2,4-trimethylcyclopentadienyldimethoxytitanium monochloride,
1,2,-dimethylcyclopentadienyltitanium trichloride,
1,2,-dimethylcyclopentadienylmethoxytitanium dichloride,
1,2,-dimethylcyclopentadienyldimethoxytitanium monochloride,
methylcyclopentadienyltitanium trichloride,
methylcyclopentadienylmethoxytitanium dichloride,
methylcyclopentadienyldimethoxytitanium monochloride,
cyclopentadienyltitanium trichloride, cyclopentadienylmethoxytitanium dichloride, cyclopentadienyldimethoxytitanium monochloride,
pentamethylcyclopentadienylmethyltitanium dichloride,
pentamethylcyclopentadienyldimethyltitanium monochloride,
1,2,3,4-tetramethylcyclopentadienylmethyltitanium dichloride,
1,2,3,4-tetramethylcyclopentadienyldimethyltitanium monochloride,
1,2,4-trimethylcyclopentadienylmethyltitanium dichloride,
1,2,4-trimethylcyclopentadienyldimethyltitanium monochloride,
1,2-dimethylcyclopentadienylmethyltitanium dichloride,
1,2-dimethylcyclopentadienyldimethyltitanium monochloride,
methylcyclopentadienylmethyltitanium dichloride,
methylcyclopentadienyldimethyltitanium monochloride,
cyclopentadienylmethyltitanium dichloride, and
cyclopentadienyldimethyltitanium monochloride.
The representative examples of the compound having at least two functional groups represented by the general formulae (C), (D) or (E) include:
ethylene glycol, 1,3-propanediol, 1,2-propanediol, (s)-(+)-1,2-propanediol,
2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol,
2-ethyl-2-methyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol,
2-methyl-2-propyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol,
1,4-butanediol, (R)-(xe2x88x92)-1,3-butanediol, (S)-(+)-1,3-butanediol,
(xc2x1)-1,2-butanediol, 2,3-butanediol, meso-2,3-butanediol,
(2R,3R)-(xe2x88x92)-2,3-butanediol, (2S,3S)-(+)-2,3-butanediol,
3,3-dimethyl-1,2-butanediol, pinacol, 1,5-pentanediol, 1,4-pentanediol,
1,2-pentanediol, 2,4-pentanediol, (2R,4R)-(xe2x88x92)-pentanediol,
(2S,4S )-(+)-pentanediol, 2-methyl-2,4-pentanediol,
(R)-(xe2x88x92)-2-methyl-2,4-pentanediol, 2,4-dimethyl-2,4-pentanediol,
2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 1,5-hexanediol,
(xc2x1)-1,2-hexanediol, 2,5-hexanediol, 2-ethyl-1,3-hexanediol,
2,5-dimethyl-2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,2-octanediol,
1,9-nonanediol, 1,10-decanediol, 1,2-decanediol, 1,12-dodecanediol,
(xc2x1)-1,2-dodecanediol, cis-1,2-cyclopentanediol, trans-1,2-cyclopentanediol,
1,3-cyclopentanediol, trans-1,2-cyclohexanediol, 1,2-cyclohexanediol,
1,4-cyclohexanediol, 2,5-dimethylcyclohexane-1,4-diol,
2,5-isopropylcyclohexane-1,4-diol, cis-1,2-cyclohexanedimethanol,
1,4-cyclohexanedimethanol, (+)-cis-p-methane-3,8-diol,
(xe2x88x92)-trans-p-methane-3,8-diol, (xc2x1)-trans-1,2-cycloheptanediol,
cis-1,2-cyclooctanediol, trans-1,2-cyclooctanediol, 1,4-cyclooctanediol,
cis-1,5-cyclooctanediol, 4,8-bis(hydroxymethyl)tricyclo[5.2.1.02,6]-decane,
(1R,2R,3S,5R)-(xe2x88x92)-pinandiol, 1,5-decalindiol, 3-cyclohexane-1,1-dimethanol,
(xc2x1)-trans-2-cyclohexane-1,4-diol, trans-p-ment-6-ene-2,8-diol,
cis -3,5-cyclohexadiene, 5-norbonene-2,2-dimethanol,
(xc2x1)-(2-endo,3-exo)-bicyclo[2.2.2]-oct-5-ene-2,3-dimethanol,
1,1,1-tris(hydroxymethyl)ethane, (R)-(+)-1,2,4-butanetriol,
(S)-(xe2x88x92)-1,2,4-butanetriol, 2-ethyl-2-(hydroxymethyl)-1,3-propanediol,
(xc2x1)-1,2,3-trihydroxyhexane, 1,2,6-trihydroxyhexane, ethanolamine,
2-hydroxyethylhydrazine, 3-amino-1-propanol, DL-1-amino-2-propanol,
4-amino-1-butanol, (xc2x1)-2-amino-1-butanol), 5-amino-1-pentanol,
DL-2-amino-1-pentanol, 6-amino-1-hexanol, 2-(2-aminoethoxy)ethanol,
2-(methylamino)ethanol, 2-(ethylamino)ethanol, 2-(propylamino)ethanol,
diethanolamine, diisopropanolamine, 2-(butylamino)ethanol,
N-methyldiethanolamine, N-ethyldiethanolamine, N-butyldiethanolamine,
triethanolamine, triisopropanolamine,
1-[N,N-bis(2-hydroxyethyl)amino]-2-propanol, catechol, 3-methylcatechol,
4-methylcatechol, 4-tert-butylcatechol, DL-3,4-dihydroxyphenylglycol,
3,5-diisopropylcatechol, 3,5-di-tert-butylcatechol, resorcinol,
2-methylresorcinol, 4-ethylresorcinol, 4-hexylresorcinol, 4-dodecylresorcinol,
5-pentylresorcinol, 5-pentadecylresorcinol, 2,5-dimethylresorcinol,
hydroquinone, methylhydroquinone, tert-butylhydroquinone,
2,3-dimethylhydroquinone, 2,5-di-tert-butylhydroquinone,
2,5-bis(1,1,3,3-tetramethylbutyl)hydroquinone, trimethylhydroquinone,
1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene,
1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene,
1,6-dihydroxynaphthalene, 2,3-dihydroxynaphthalene,
2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene,
bis(2-hydroxyphenyl)methane, (xc2x1)-hydrobenzoin, meso-hydrobenzoin,
(R,R)-(+)-hydrobenzoin, (S,S )-(xe2x88x92)-hydrobenzoin, benzopinacole,
1,4-benzenedimethanol, xcex1,xcex1,xcex1xe2x80x2,xcex1xe2x80x2-tetramethyl-1,4-benzenedimethanol,
1,5-dihydroxy-1,2,3,4-tetrahydronaphthalene, 2,2xe2x80x2-biphenyldimethanol,
3-(3,5-di-tert-butyl-4-hydroxyphenyl)-1-propanol,
(xc2x1)-1-phenyl-1,2-ethanediol, (S)-(+)-1-phenyl-1,2-ethanediol,
(R)-(xe2x88x92)-1-phenyl-1,2-ethanediol, (R)-(+)-1,1,2-triphenyl-1,2-ethanediol,
4,4xe2x80x2-biphenol, phenylhydroquinone, bis(4-hydroxyphenyl)methane,
4,4xe2x80x2-isopropylidenediphenol, 4,4xe2x80x2-(1,4-diisopropylidenediphenol),
2,2-bis(4-hydroxy-3-methylphenyl)propane,
1,1,1-tri(4-hydroxyphenyl)ethane, meso-hexestrol, 1,2-ethanedithiol,
1,3-propanedithiol, 1,2-propanedithiol, 1,4-butanedithiol, 1,3-butanedithiol,
1,5-pentanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol, 1,9-nonanedithiol,
2-mercaptoethanol, 1-mercapto-2-propanol, 3-mercapto-2-butanol, n
3-mercapto-1,2-propanediol, 2,3-dimercapto-1-propanol, dithiothreitol,
dithioerythreitol, 2-mercaptoethyl ether, 1,4-dithiane-2,5-diol,
2,5-dimethyl-2,5-dihydroxy-1,4-dithiane,
1,5,9,13-tetrathiacyclohexadecane-3,11-diol,
1,5,9,13,17,21-hexathiacyclotetracosane-3,11,19-triol, ethyleneamine,
1,3-diaminopropane, 1,2-diaminopropane, 1,4-diaminobutane,
1,2-diamino-2-methylpropane, 1,6-hexanediamine, 1,7-diaminoheptane,
1,8-diaminooctane, 2,5-dimethyl-2,5-hexanediamine, 1,9-diaminononane,
1,10-diaminodecane, 1,12-diaminododecane, spermidine,
4,4xe2x80x2-methylenebis(cyclohexylamine),
4,4xe2x80x2-methylenebis(2-methylcyclohexylamine), 1,4-diaminocyclohexane,
1,3-cyclohexanebis(methylamine), 1,8-diamino-p-methane,
4,4xe2x80x2-trimethylenedipiperidine, 2-piperidinethanol, 3-piperidinethanol,
4-hydroxypiperidine, 4,4xe2x80x2-trimethylenebis(1-piperidinethanol),
2,2,6,6-tetramethyl-4-piperidinol, piperazine, 2,6-dimethylpiperazine,
1,4-bis(2-hydroxyethyl)piperazine, homopiperazine, 1,4,7-triazacyclononane,
1,5,9-triazacyclododecane, cyclene, 1,4,8,11-tetraazacyclotetradecane,
1,4,8,12-tetraazacyclotetradecane, 2-anilinoethanol, N-phenyldiethanolamine,
3-aminophenol, 3-aminothiophenol, 4,4xe2x80x2-ethylenedianiline,
3,3xe2x80x2-methylenedianiline, 4,4xe2x80x2-ethylenedianiline, 4-aminophenyl ether,
4-aminophenol, 4-aminophenethyl alcohol,
4,4xe2x80x2-methylenebis(2,6-dimethylaniline), 4,4xe2x80x2-methylenebis(2,6-diethylaniline),
4,4xe2x80x2-methylenebis(2,6-diisopropylaniline), 3,3xe2x80x2,5,5xe2x80x2-tetramethylbenzidine,
1,4-phenylenediamine, N,Nxe2x80x2-diphenyl-1,4-phenylenediamine,
2,7-diaminofluorene, N,Nxe2x80x2-dibenzylethylenediamine, (xc2x1)-syneprine,
4-hydroxy-4-phenylpiperidine, 1,3-bis(phenylphosphino)propane,
1,2-bis(phophino)benzene, 4,4xe2x80x2-isopropylidenedicyclohexanol,
4,4xe2x80x2-(hexafluoroisopropyllidene)diphenol,
4,4xe2x80x2-(phenylenediisopropylidene)bisphenol and 1,2-bis(phosphino)ethane.
The metallocene catalysts are prepared by reacting the metallocene compounds (A) or (B) with the compounds having at least two functional groups (C), (D) or (E) in an organic solvent. The molar ratio of transition metal of the metallocene compound to the compound having at least two functional groups is in the range of 1:0.01xcx9c1:1000 and preferably 1:0.1xcx9c1:20. The reaction temperature is in the range of xe2x88x9280xc2x0 C.xcx9cxe2x88x92300xc2x0 C. and preferably 0xc2x0 C.xcx9c150xc2x0 C. The weight ratio of an organic solvent to the reactants is in the range of 0.1:1xcx9c1000:1 and preferably 1:1xcx9c100:1.
The metallocene catalyst according to the present invention is employed with a co-catalyst in order to prepare polystyrene having a syndiotactic structure or polyolefin having improved physical properties. The co-catalyst is an organometallic compound or a mixture of non-coordinated Lewis acid and alkylaluminium as is widely known. The organometallic compound is an alkylaluminoxane or an organoaluminium compound. The representative examples of alkylaluminoxane are methylaluminoxane (MAO) and modified methylaluminoxane (MMAO).
The organoaluminium compound is aluminoxane having the structural unit represented by the general formula (F). There are aluminoxane having a chain structure represented by the general formula (G) and aluminoxane having cyclic structure represented by the general formula (H). 
wherein Rxe2x80x2 is an alkyl group of C1-6 and q is an integer of 0 to 100.
The olefin or styrene polymerization employs a new metallocene catalyst according to the present invention and a co-catalyst such as organometallic compound. The component ratio of the new metallocene catalyst to organometallic compound is the same as the molar ratio of a transition metal (IV) in the new metallocene catalyst to the aluminium in the organometallic compound. That is, the molar ratio of the transition metal to aluminium is in the range of 1:1 to 1:1xc3x97106 and preferably in the range of 1:10 to 1:1xc3x97104.
The co-catalyst used in the present invention is a mixture of non-coordinated Lewis acid and alkylaluminium. Examples of non-coordinated Lewis acid include N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, triphenylcarbenium tetrakis(pentafluorophenyl)borate, and ferrocerium tetrakis(pentafluorophenyl)borate. Examples of alkylaluminium include trimethylaluminium, triethylaluminium, diethylaluminium chloride, triisobutylaluminium, diisobutylaluminium chloride, diisobutylaluminium hydride, tri(n-butyl)aluminium, tri(n-propyl)aluminium, and triisopropylaluminium.
The molar ratio of non-coordinated Lewis acid to a transition metal in the catalyst system according to the present invention is preferably in the range of 0.1:1xcx9c20:1. The molar ratio of a transition metal to alkylaluminium in the catalyst system is preferably in the range of 1:1xcx9c1:3000 and more preferably in the range of 1:50xcx9c1:1000.
The reaction temperature for styrene or olefin polymerization by using the catalyst system according to the present invention is preferably in the range of 0xcx9c140xc2x0 C. and more preferably in the range of 30xcx9c100xc2x0 C.
The monomers for polymerization by using the catalyst system according to the present invention are a styrene, a styrene derivative, or an ethylenically unsaturated compound. Those monomers can be homopolymerized or copolymerized.
The styrene and styrene derivative are represented by the general formulae (I) or (J): 
wherein J1 in the general formula (I) is a hydrogen atom; a halogen atom; or C, O, Si, P, S, Se or Sn, and m is an integer of 1 to 3, J1 may be different substituents independently of each other if m is 2 or 3; and J1 in the general formula (J) is the same as defined in the formula (I), J2 is a substituent composed of 2 to 10 carbon atoms having at least one unsaturated bond, m is an integer of 1 to 3, and n is an integer of 1 or 2, in which the benzene ring may independently have different substituents if m is over 2 and n is 2.
The illustrative examples of the compounds represented by the general formula (I) include alkylstyrene, halogenated styrene, halogen-substituted alkylstyrene, alkoxystyrene, vinylbiphenyl, vinylphenylnaphthalene, vinylphenylanthracene, vinyphenylpyrene, trialkylsilybiphenyl, trialkylstannylbiphenyl compound, alkylsilystyrene, carboxymethylstyrene, alkylester styrene, vinylbenzenesulfonic acid ester, and vinylbenzyldialkoxy phosphate.
The alkylstyrene includes styrene, methylstyrene, ethylstyrene, n-butylstyrene, p-methylstyrene, p-tert-butylstyrene, and dimethylstyrene.
The halogenated styrene includes chlorostyrene, bromostyrene, and fluorostyrene.
The halogenated alkylstyrene includes chloromethylstyrene, bromomethylstyrene, and fluoromethylstyrene.
The alkoxystyrene includes methoxystyrene, ethoxystyrene, and butoxystyrene.
The vinylbiphenyl includes 4-vinylbiphenyl, 3-vinylbiphenyl, and 2-vinylbiphenyl.
The vinylphenylnaphthalene includes 1-(4-vinylphenylnaphthalene), 2-(4-vinylphenylnaphthalene), 1-(3-vinylphenylnaphthalene), 2-(3-vinylphenylnaphthalene), and 1-(2-vinylphenylnaphthalene).
The vinylphenylanthracene includes 1-(4-vinylphenylanthracene, 2-(4-vinylphenyl)anthracene, 9-(4-vinylphenyl)anthracene, 1-(3-vinylphenyl)anthracene, 9-(3-vinylphenyl) anthracene, and 1-(2-vinylphenyl)anthracene.
The vinylphenylpyrene includes 1-(4-vinylphenyl)pyrene, 2-(4-vinylphenyl)pyrene, 1-(3-vinylphenyl)pyrene, 2-(3-vinylphenyl)pyrene, 1-(2-vinylphenyl)pyrene, and 2-(2-vinylphenyl)pyrene.
The trialkylsilyvinylbiphenyl includes 4-vinyl-4-trimethylsilybiphenyl.
The trialkylstannylbiphenyl includes 4-vinyl-4-triethylstannylbiphenyl.
The alkylsilystyrene includes p-trimethylsilystyrene, m-trimethylsilystyrene, o-trimethylsilystyrene, p-triethylsilystyrene, m-triethylsilystyrene, and o-triethylsilystyrene.
The illustrative examples of the compounds represented by the general formula (J) include divinylbenzene such as p-divinylbenzene and m-divinylbenzene; trivinylbenzene; and aryl styrene such as p-arylstyrene and m-arylstyrene.
Also, the ethylenically unsaturated monomer is represented by the general formula (K): 
wherein E1, E2, E3 and E4 are respectively functional groups which are selected the group of a hydrogen atom; a halogen atom; and substituents containing at least one atom selected from the group consisting of C, O, Si, P, S, Se and Sn. E1, E2, E3 and E4 are respectively able to have functional groups which are different from each other.
The illustrative examples of the compounds represented by the formula (K) are xcex1-olefin, cyclic olefin, diene, vinylketone, acrolein, acrylonitrile, acryloamide, acrylic acid, and vinyl acetate.
Examples of xcex1-olefin include ethylene, propylene, 1-butene, 1-hexene, and 1-octene.
Examples of cyclic olefin include cyclobutene, cyclopentene, cyclohexene, 3-methylcyclopentene, 3-methylcyclohexene, and norbonene.
Examples of diene include 1,3-butadiene, isoprene, 1-ethoxy-1,3-butadiene, and chloroprene.
Examples of vinylketone include methylvinylketone, phenylvinylketone, ethylvinylketone, and n-propylvinylketone.
Examples of acrolein include acrolein, and metacrolein.
Examples of acrylonitrile include vinylidenecyanide, methoxyacrylonitrile, and phenylacrylonitrile.
Examples of acryloamide include N-methylacryloamide, N-ethylacryloamide, and N-isopropylacryloamide.
Examples of acrylic acid include aryl acrylate, isopropyl acrylate, ethyl acrylate, and acrylic acid chloride.
Examples of vinyl acetate include vinyl acetate and vinyl thioacetate.
A method of polymerization in accordance with the present invention comprises contacting monomers selected from the group consisting of styrenes, its derivatives, or ethylenically unsaturated compounds with the catalyst system according to the present invention. Monomers, co-catalyst and metallocene catalyst of this invention may be added in a row to a polymerization reactor. Also, after reacting the metallocene compound and the compound having at least two functional groups in a polymerization reactor, and co-catalyst and monomers may be added in a row to the polymerization reactor. Further, after reacting the metallocene compound and the compound having at least two functional groups in a polymerization reactor being filled with monomers, and co-catalyst may be added to the polymerization reactor. Further, the polymerization may be performed by reacting the metallocene compound and the compound having at least two functional groups in a reactor being filled with co-catalyst, aging the resultant solution, and adding the aged solution to the polymerization reactor being filled with monomers. The resultant solution is preferably aged at the temperature of 0xcx9c150xc2x0 C. for 1xcx9c60 min. The copolymerization of monomers selected from the group consisting of styrenes, its derivatives, ethylenically unsaturated compounds and a mixture thereof may be carried out as in the polymerization above.
The present invention may be better understood by reference to the following examples which are intended for purposes of illustration and are not to be confined as in any way limiting the scope of the present invention, which is defined in the claims appended hereto.